Air-pump.



H. A. FLEUSSP AIR PUMP.

APPLICATION FILED JUNE 24, 1912.

Patents 3d Jan. 14, 1913.

HENRY ALBERT FLEUSS, OF THATOHAM, ENGLAND,

ENGINEERING COMPANY, LIMITED, OF

ASSIG-NOR TO THE PULSOMETER READING, ENGLAND.

AIR-PUMP.

Specification of Letters Patent.

Patented Jan. 14,1913.

Application filed. June 24, 1912. Serial No. 705,493.

To all whom it may concern Be it known that I, HENRY ALBERT FLEUss, a subject of the King of Great Britain, residing at Dunstan Lodge, 'Thatcham, Berkshire, England, have invented new and useful Improvements in Air-Pumps, of which the following is a specification.

This invention relates to air pumps in which the air delivery valve is at the top of a vertical pump cylinder and opens upward into a receiving chamber the lower partof which is filled with liquid as for example with oil. In pumps of this class the delivery valve is usually lifted by the piston as it is brought to the top of its upward stroke and air and oil previously contained in the cylinder is then delivered past the valve into the receiving chamber while on the first portion of the down stroke of the piston some oil is allowed to pass back into the cylinder above the piston by the valve remaining held open by the piston during the first portion of its downward stroke.

Such pumps as heretofore constructed if worked at too high a speed lose their efficiency owing to the fact that suflicient time is then not allowed for the air to separate from the oil before it passes back into the cylinder on the downward stroke of the piston and the vacuum that can be obtained by the downward stroke of the piston is thereby impaired. To remedy this I make the lower end of the receiving chamber to open into a bath of liquid surrounding its exterior and also make openings through the upper end of the receiving chamber through which liquid rising upward through the chamber can overflow and pass downward to reenter the chamber at its lower end.

The air and oil injected upward past the delivery valve create an upward current through the interior of the chamber and a downward return current on its exterior so that the liquid passing back into the chamher through the openings in its lower end is always liquid from which air has had time to separate and when the piston descends in the pump cylinder the liquid drawn into the pump cylinder is practically free from air.

In order to insure that the air and oil ejected past the delivery valve shall be directed upward into the interior of the receiving chamber and not allowed to spread laterally, I preferably make the underside of the pump cylinder cover to cone upward to a valve seat at its center as heretofore and as heretofore I make the valve in the form of an inverted cone which near its upper end fits into the valve seat which is correspondingly coned and of small depth so that the lower part of the coned valve extends downward for some distance below the valve seat. The slope of the coned sides of the valve I make such that the sides if prolonged would meet the solid inner sides of the receiving chamber thus when the valve is lifted and oil and air rush upward past its sloping sides they come against the inner sides of the receiving chamber and are deflected upward and not allowed to spread. laterally.

Figures 1 and 2 show vertical sections of two examples of air pumps constructed according to my invention.

In Fig. 1 a; is the pump barrel or cylinder, 5 the delivery valve at its upper end, a the inlet for air to pass to the interior of the pump barrel from a chamber 05 from which a pipe 6 extends to the vessel to be exhausted. f is the receiving chamber above the top of the pump barrel, 9 are openings through the lower end of the sides of this chamber and h are openings through their upper end, 2' is an outer chamber containing oil by which the receiving chamber f is surrounded. 70 is the piston and Z the piston rod extending as usual through the center of the delivery valve Z) and through the cover of the receiving chamber f. m is a coiled spring by which the delivery valve is pressed downward.

In Fig. 2 the parts corresponding to those shown in Fig. 1 are marked with similar letters of reference. In this example the receiving chamber f in place of being secured to the cover of the pump barrel as shown in Fig. 1 is held up to. the cover of the outer chamber 2'. The outlet from the upper end of this chamber is adapted to have a pipe led away from it to the suction inlet of a second pump.

What I claim is 1. In an air pump the combination of a pump barrel, a delivery valve at its upper end, a receiving chamber above the top of the pump barrel, a bath of oil or like liquid outside the receiving chamber and openings both at top and bottom of the receiving chamber by which liquid can pass to and from the bath of liquid and the interior of the receiving chamber.

2. The combination of a pump barrel, a cover closing the top of this barrel coned upward on its underside to a valve seat at its center, a valve resting at its upper end in this seat and coned downward and extending for some distance below the seat, a receiving chamber above the top of the 10 pump barrel, an outer casing containing oil or like liquid surrounding the receiving chamber and openings both at top and bottom of the receiving chamber by which liquid can pass to and from the bath of liquid and the interior of the receiving chamber.

HENRY ALBERT FLEUSS. WVitnesses:

R. VVESTACOTT, O. J WORTH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G. 

